Automatic adjustable double telephone-receiver



I (No Model.) I 2 Sheets-Sheet 1.

- D. G BARNARD.

AUTOMATIC ADJUSTABLE DOUBLE TELEPHONE REGEIVER.

No. 303,553. Patented Aug. 12, 1884.

E E V =i: c' I Z (No Model.)

2 SheetsSheet 2.

11G. BARNARD.

AUTOMATIC ADJUSTABLE DOUBLE-TELEPHONE REGBIVER- Patented Aug. 12,1884.

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DANIEL G. BARNARD, OF \VINSLOVV,

NEW JERSEY, ASSIGNOR OF THREE- FOURTHS TO \VILLIAM O. HAY, HELEN H. BERNADON, AND ANNIE D. SQUIRE, ALL OF SAME PLACE, AND AUGUSTA H. OOOHRAN AND GEORGE OOCHRAN, OF PHILADELPHIA, PENNSYLVANIA.

AUTOMATIC ADJUSTABLE DOUBLE TELEPHONE-=RECEIVER.

SPECIFICATION forming part of Letters Patent No. 303,553, dated August 12, 1884.

Appliea't'n'on filed May 1, 1884.

To all whom it may concern:

Be it known that I, DANIEL G. BARNARD,

residing in Vinslow, in the county of Camden and State of New Jersey, have invented a new and useful Improvement in Automatic Adjustable Double Telephone-Receivers, of which the following is a specification, reference being had to the annexed drawings, forming a part thereof.

The object of my invention is to improve the double telephone-receiver for which Letters Patent N 0. 280,116 were granted tome June 26, 1883.

My invention consists in the combination, I 5 with two diaphragm'cells, of a holder composed of two arms hinged together and pivoted to the diaphragm-cells, and drawn toward each other by a bow-spring attached to the free ends of the said arms, and forming an electrical connection between the terminals of the two receiver-bobbins.

Figure 1 is a side elevation of my improved automatic adjustable double telephone-re ceiver. Fig. 2 is a side elevation of the reverse sideof myimproved telephone-receiver. Fig. 3 is a transverse section of the diaphragm-cell and of the parts contained therein. Fig. 4 is a rear view of the diaphragm-cell with the cap removed to show the receiver-magnet.

Similar letters of reference indicate like parts in the different figures of the drawings.

Two levers, A, curved sufficiently to receive between them the head of the user of the telephone, are provided with handles B, and are connected together at the upper ends of the handles by a hinge, C,

To the free ends of each curved lever A are secured two curved metallic arms,D D,whieh are apertured at their free ends to receive the pivotal screws to, which pass through the arms D D into diametricallyopposite sides of the diaphragm-cells E, forming pivots upon which the cells may swing to adapt themselves to the ears of the user. The screws a are connected with the terminals of the telephone-bobbin b, and serve to conduct the telephonecurrent through the sides of the diaphragm-cell. The

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ends of the arms D of the opposite levers A are connected with each other by awire bowspring, F,whieh conforms to the general curve 0 of the lovers A, and draws them toward each other, and at the same time serves as an electrical conductor between the bobbins of the two diaphragm-cells. The ends of the arms D, which are secured to the levers A, are pro- 5 longed toward the hinge G, and provided at their extremities with binding-posts G,for receiving the usual telephone-conductor. WVhen the diaphragnreells E are drawn toward each other by the spring F, the handles B are separated, and to limit the movement of the levers A a hook, 0, extends from one handle into a mortise in the other in position to engage a pin, 0, passing transversely through the mortise when the handles are separated. The diaphragm-cells E each contains a bobbin, I), surrounding the end of a permanent magnet, d, which is curved in a spiral, e, to bring it within the compass of the cell. The magnet d is clamped by screws f against the fillet g, formed in the diaphragmcell. The diaphragmcell contains the usual diaphragm, 71, which is opposed to the magnet, and is partly coverec by the aperturcd cap 1.

The automatic adj ustable telephone-receiver 7 5 is applied to the cars by separating the diaphragm-cells E by pressing on the handles B, then placing the head between them, then releasing the handles, so that the bow-spring F may draw the diaphragm-cells against the ears. .80 WVhen thus applied, both ears are used, and all extraneous sounds are effectively shutout. By this construction the volume of sound is greatly increased, and faint sounds are rendered more effective.

My improved automatic adjustable receiver facilitates telephonic communication in noisy places, and permits of receiving telephonic messages by currents too weak to operate the ordinary receiver effectively. It is therefore 0 especially adapted to long-distance telephony, where the currents arriving at the receiving end of the telephone-line are but a fraction of the current sent out by the transmitter.

Having thus described my invention, what I F, secured to the said arms and forming an claim as new, and desire to secure by Letter electrical connection between the same, and Patent, is arms D, prolonged toward the hinge of the le- 1. The combination, with the curved levers vers A, and provided with binding-posts G, as

5 A, hinged to each other and provided with specified.

handles B of the bow-sprin F for pressin the free ends of the levers together, as d; DANIEL BARNARD' scribed. Witnesses:

2. The combination, with the hinged levers GEO. BARTALOTT,

re A, of diaphragm-cells E, arms D; bow-spring GEO. P. BARTALOTT. 

